Running LTP testcases/kernel/io/direct_io/test_dma_thread_diotest7 causes IO errors in the guest. There are no IO errors on the host.
Kernel Linux 3.0.0-rc* Using a standard emulated IDE -hda image. I tried a few qemu versions, it happens at least with the one in FC14 and with 0.14. qemu master doesn't boot and ends with a spinlock lockup. Writing file _dma_thread_test_0010.tmp. Writing file _dma_thread_test_0011.tmp. Writing file _dma_thread_test_0012.tmp. ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 ata1.00: BMDMA stat 0x5 ata1.00: failed command: WRITE DMA EXT ata1.00: cmd 35/00:00:e9:6c:ba/00:04:00:00:00/e0 tag 0 dma 524288 out res 41/04:00:e9:6c:ba/04:00:e9:6c:ba/e0 Emask 0x1 (device error) ata1.00: status: { DRDY ERR } ata1.00: error: { ABRT } ata1.00: configured for MWDMA2 ata1: EH complete ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 ata1.00: BMDMA stat 0x5 ata1.00: failed command: WRITE DMA EXT ata1.00: cmd 35/00:00:e9:6c:ba/00:04:00:00:00/e0 tag 0 dma 524288 out res 41/04:00:e9:6c:ba/04:00:e9:6c:ba/e0 Emask 0x1 (device error) ata1.00: status: { DRDY ERR } ata1.00: error: { ABRT } ata1.00: configured for MWDMA2 ata1: EH complete ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 ata1.00: BMDMA stat 0x5 ata1.00: failed command: WRITE DMA EXT ata1.00: cmd 35/00:00:e9:6c:ba/00:04:00:00:00/e0 tag 0 dma 524288 out res 41/04:00:e9:6c:ba/04:00:e9:6c:ba/e0 Emask 0x1 (device error) ata1.00: status: { DRDY ERR } ata1.00: error: { ABRT } ata1.00: configured for MWDMA2 ata1: EH complete ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 ata1.00: BMDMA stat 0x5 ata1.00: failed command: WRITE DMA EXT ata1.00: cmd 35/00:00:e9:6c:ba/00:04:00:00:00/e0 tag 0 dma 524288 out res 41/04:00:e9:6c:ba/04:00:e9:6c:ba/e0 Emask 0x1 (device error) ata1.00: status: { DRDY ERR } ata1.00: error: { ABRT } ata1.00: configured for MWDMA2 ata1: EH complete ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 ata1.00: BMDMA stat 0x5 -- a...@linux.intel.com -- Speaking for myself only